Have I mentioned gamma knife surgery? Perhaps in passing? Here's a brain dump; I hope it is not a repeat.
===
Some friends told me about "gamma knife surgery". It's used instead of open skull surgery, for hard-to-reach brain tumours. I followed up with web searches and I asked my radiation oncologist.
... "Gamma knife surgery" (GKS) uses -- you guessed it -- gamma rays to destroy a tumour. The rays are focused on a 3D location, the tumour. At the focal point of the rays, whatever cells are there -- cancerous cells of the tumour -- are cooked and destroyed. The tumour is destroyed in just a minute or two, with no need to open the skull.
... A Queensland hospital can do GKS -- for about $26,000. If it's like my own radiation treatment as an outpatient, Medicare will pay for two thirds and private health insurance pays zero.
... GKS requires absolutely no movement of the head during radiation. Metal studs are drilled into the skull then attached to the table, to prevent the head from moving.
According to my oncologist, there's a lot of marketing. I did find a doctor in Chicago who offers GKS. He has a million dollar machine. Judging by his website he spends at least that much on glossy marketing. I didn't find any cost for the patient.
... A similar knifeless surgery is available in Perth, "cyber knife surgery" (Cyber). Actually, it is written as "Cyberknife Surgery", definitely a trade name.
... Its operating principle is similar to GKS, zapping a 3D area of tumour. Stereotactic radiation therapy, I think it's called.
... Cyber zaps radiation from a robot, which whizzes round to get the best shot. The patient's head must still be still but Cyber can track and allow for some movement. It does this by tracking bits of gold inserted under the scalp.
To me, Cyberknife is a more advanced version of Gamma Knife. And Cyber is a lot easier for the patient.
... Cyberkife is available in Western Australia. Cost to patient: $zero.
===
Are either of these useful to me?
I have a particular type of brain cancer. A tumour in the brain could be caused by any one of several types of cancer. To know how to treat my cancer it must first be identified... My tumour had already had a bad effect (it caused me to have an epileptic fit) so it needed to be removed.
The only way to positively identify the cancer is to look at a sample under a microscope (or whatever). To get a sample, the skull is opened up. This is always the first step of cancer treatment. Gamma or Cyber or other radiation are "never" the first option...
If the tumour is wrapped up inside the brain and it is too dangerous to try to get a knife to it, radiation may be the first option. Not a satisfactory option, though, since the type of cancer remains uncertain. My own tumour was at the outer edge of the brain; relatively easy to open up the skull, stick a knife in and gouge out the lump.
After open-head surgery -- once the cancer is identified -- it was time for radiation. This time, spot-on accuracy is *not* required. Sort of...
A tumour is a visible lump. It will be surrounded by cancer cells -- microscopic cells -- in the surrounding tissue. It is these microscopic and effectively invisible cells which will grow into new tumours.
If you have (for example) lung cancer, a tumour can be removed. The surgeon may also take out surrounding -- apparently healthy -- lung tissue. The idea is to remove both tumour and surrounding cancerous cells, to reduce the chance of regrowth. Take out some "healthy" lung, it doesn't matter, there's plenty of spare lung.
Take out "healthy" cells in the brain -- and the results could be disastrous. Loss of vision, loss of motor control, loss of life... depends on what part of the brain is removed. So cancer surgery on the brain removes as little "healthy" tissue as possible. Sounds like a job for Gamma or Cyber knife? Not really...
The tumour is visible, it is removed. The surrounding tissue, for a cm or so all round, may contain cancerous cells -- "seed cells" for future tumours. Zap them with a Gamma or Cyber knife and it's as though the tissue was cut out surgically: loss of this, loss of that, loss of the other... Serious stuff. To be avoided. As much as possible.
My own radiation treatment -- as far as I understand it -- zapped those probably-infected surrounding brain tissues. *Gently* zapped. The aim is to destroy the sensitive cancer cells and leave the less sensitive healthy cells still alive. As much as possible. So yes I will lose some brain cells but I should lose even more cancerous cells. (Take my word for it. As I take my doctors' word...)
My radiation was at a lower intensity than either Gamma or Cyber knife. Lower intensity, broader spread, repeated daily over several weeks rather than just once.
Cancerous cells will have been killed, the more the merrier. Other cells have been damaged. My hair, for example, was zapped and disappeared in a large circle on the side of my head. The hair is doing its best to regrow. Damaged "good" cells inside my skull are also -- I hope -- doing their best to recover.
Neither Gamma nor Cyber are useful for my treatment, nor are they necessary. I'm lucky, my tumour was clearly defined and relatively accessible. Whatever regrows -- when it does -- I may not be so lucky. We'll deal with that when it happens!
Meanwhile, I'm continuing the chemo.
===
"Chemo"... it's short for chemotherapy: "the treatment of disease by the use of chemical substances, especially the treatment of cancer by cytotoxic and other drugs." That's when I swallow four capsules a day for one week in four. It works much the same way as my radiation.
The drugs I swallow are "cytotoxic": "toxic to living cells." The particular drug that I swallow is especially toxic to the living cells of my type of cancer (glioblastoma multiforme) (GBM). That's why it's so important to identify the type of cancer: so that the appropriate drug is used for the chemo treatment.
As with radiation, the chemo will also kill healthy cells... but not as effectively as it kills my GBM cancer cells.
I have a week of killing cancer cells -- and some non-cancer cells. Then three weeks to rebuild the non-cancer cells. That, I guess, explains some of my tiredness: I am using energy on regrowing and repairing essential "good" body cells.
Like the radiation, chemo should kill more cancer than healthy cells. It knocks me around but I come out ahead. So far :-)
===
The technology -- and treatment -- are amazing. It would be fascinating to watch -- especially the Cyberknife robot... but really, all the patient sees is the inside of a face-fitting mask.
The Gamma knife suggestion lead me to all sorts of interesting -- and relevant -- information. Enough information to convince me to return to my standard state: put my life in the hands of experts and let them make all the difficult decisions.
And hope that the need for further knife-work -- gamma, cyber or stainless steel -- is delayed for as long as possible.
Dr Nick Lethbridge / Consulting Dexitroboper
... Agamedes Consulting / Problems ? Solved
===
"Even if a million people repeat the same nonsense, it is still nonsense" … Anatole France (paraphrased)
===
I hope further intrusion into your cranium is not required as the chemo has worked wonderfully. Cheers Col
ReplyDelete